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1.
陈慕华  陈燕青  陈思  朱新宝 《化工进展》2014,33(5):1201-1204,1241
以活性炭负载钛酸四丁酯[Ti(OBu)4/AC]为催化剂,用于催化合成二甘醇二苯甲酸酯(DEDB)。通过实验确定了合成DEDB的适宜工艺条件:n(BA)∶n(DEG) = 2∶1、催化剂用量为1.25%,带水剂用量为20.0%,反应温度为200℃,反应时间为7h,该反应条件下酯化率可达98.1%。催化重复使用实验表明该催化剂具有良好的稳定性。同时建立了该酯化合成的表观动力学模型,得到反应速率方程为:rA=6.28× 109exp CACB。  相似文献   

2.
梁世强  穆筱梅 《精细化工》2005,22(9):685-687
以玻璃珠为载体,制备了固体超强酸SO42-/TiO2催化剂,用于催化合成二甘醇二苯甲酸酯(DEDB)。通过实验确定了合成DEDB的适宜工艺条件:回流温度为165~170℃,m(甲苯)/m(二甘醇)=0.5,n(苯甲酸)/n(二甘醇)=2.2,m(催化剂)/m(二甘醇)=0.5,反应时间4 h,在该条件下,酯化率可达99.6%。该催化剂经过10次重复使用,活性每次平均下降2.9%。  相似文献   

3.
李志成  方煜  胡文浩 《广东化工》2012,39(5):300+302-300,302
在对甲苯磺酸催化下、使用环己烷作带水剂,以苯甲酸和二甘醇为原料合成环保增塑剂二甘醇二苯甲酸酯(DEDB)。研究考察了酸醇摩尔比、催化剂用量、带水剂用量和反应时间等因素对产率的影响。确定了最佳工艺条件:n(苯甲酸)∶n(二甘醇)=2.0∶1.1、催化剂用量(以苯甲酸的摩尔数计)3.0%、环己烷12 mL、回流反应时间8 h,目标产品的产率为98.0%。  相似文献   

4.
磷钨酸铝催化合成二甘醇二苯甲酸酯   总被引:9,自引:0,他引:9  
蒋维 《化学世界》2001,42(2):75-78
开发了一种用磷钨酸铝催化合成二甘醇二苯甲酸酯 (DEDB)的新方法。研究了催化剂用量、酸 /醇摩尔比、带水剂用量和反应时间对 DEDB收率的影响 ,用正交试验确定了合成 DEDB的最佳工艺条件为 :催化剂∶反应物 =2∶ 1 0 0 (质量分数 ) ,酸∶醇 =2 .1∶ 1 (摩尔比 ) ,带水剂甲苯∶反应物 =1∶ 3.5(质量分数 ) ,反应时间 4h,反应温度为 1 60~ 1 80°C。在此条件下 ,DEDB收率超过95%。催化剂可重复使用多次。  相似文献   

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磷钨酸铝催化合成二革醇二苯甲酸酯   总被引:2,自引:0,他引:2  
蒋维 《化学世界》2001,42(2):75-78
开发了一种用磷钨酸铝催化合成二甘醇二苯甲酸酯(DEDB)的新方法,研究了催化剂用量、酸/醇摩尔比、带水剂用量和反应时间对DEDB收率的影响,用正交试验确定了合成DEDB的最佳工艺条件为:催化剂:反应物=2:100(质量分数),酸:醇=2.1:1(摩尔比),带水剂甲苯:反应物=1:3.5(质量分数),反应时间4h,反应温度为160-180℃。在此条件下,DEDB收率超过95%。催化剂可重复使用多次。  相似文献   

6.
以三甘醇和异辛酸为原料,在活性白土的作用下,催化酯化合成三甘醇二异辛酸酯。考察酸醇物质的量比、反应时间、催化剂用量、带水剂用量等条件对酯化反应的影响,确定最佳合成工艺条件。合成三甘醇二异辛酸酯的最佳条件为酸醇物质的量比为4∶1,反应时间为5h,催化剂用量为8%,带水剂用量为33%,三甘醇转化率可达93.45%。催化剂不经任何处理重复使用3次后,三甘醇转化率有所下降,但催化剂经过再生后,三甘醇转化率可达93.2%,产品经气相色谱分析三甘醇二异辛酸酯含量为77.01%,三甘醇一异辛酸酯含量是14.48%。  相似文献   

7.
将酸性离子液体1-丁基磺酸-3-甲基咪唑对甲苯磺酸盐([(CH2)4SO3HMIm]TS)分别通过凝胶包埋、浸渍、嫁接的方法固定到层析Si O2上,考察其催化合成二甘醇二苯甲酸酯(DEDB)的效果。研究发现凝胶包埋法制备的催化剂NJ-4.0效果最好。通过实验确定了最佳工艺条件为:反应温度为165℃,反应时间为4 h,n(苯甲酸)∶n(二甘醇)=2.2∶1(二甘醇为0.1 mol),催化剂NJ-4.0质量为二甘醇质量的8%,该条件下合成DEDB的产率为86.2%。  相似文献   

8.
二苯甲酸二甘醇酯(简称DEDB是一种性能优良的增塑剂,其性能稳定,与PVC、聚醋酸乙烯酯、聚乙烯缩了醛等树脂相容性好,增塑效果佳,而且体积电阻率大,耐油污性好.产品成本低,因而具有良好的实用价值。本文介绍利用直接酯化法合成DED,将苯甲酸、二甘醇以一定比例加入到带有搅拌器、分水器及温度计的烧瓶中,用Al2O3作催化剂,在180-210C进行反应,每小时测定酸值一次,反应完毕后进行减压蒸馏,收集0.67kPa下的产品。经多次实验,得到最佳合成工艺条件是:苯甲酸与二甘醇摩尔配比为1:0.8.催化剂用量为苯甲酸量的8%,反应温…  相似文献   

9.
研究了在实验室条件下,以硫酸、对甲苯磺到为催化剂合成二甘醇二醋酸酯的方法。着重考察了原料配比、反应时间、催化剂及其用量等因素对反应的影响,结果表明,硫酸对反应具有较高的催化活性。当n(醋酸):n(二甘醇)=2.4:1,反应时间为4.5h,催化剂硫酸的加入量为二甘醇质量(W)的1.5%,反应温度不高于200℃时,其酯含量为99.7%,产率为80.2%。  相似文献   

10.
魏民  金环年  杨青松 《辽宁化工》2003,32(9):372-374
以硅胶为载体,制备了固载磷钨酸酸式铯盐(Cs2.5H0.5PWl2O40/SiO2)催化剂,并用于催化合成二甘醇二苯甲酸蘸(DEDB)。研究了催化剂制备条件对催化性能的影响和反应条件对蘸化反应的影响。在n(酸)/n(醇)=2.2、催化剂用量为0.7%、反应温度80℃、反应时间4h、带水剂N2流量250mL的条件下,酯化率可达到99.67%。催化剂重复试验表明,该催化剂具有良好的活性与稳定性。  相似文献   

11.
Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

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Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

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收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

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收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

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Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.  相似文献   

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Ethanol and α-pinene were tested as attractants for large wood-boring pine beetles in Alabama, Florida, Georgia, North Carolina, and South Carolina in 2002–2004. Multiple-funnel traps baited with (−)-α-pinene (released at about 2 g/d at 25–28°C) were attractive to the following Cerambycidae: Acanthocinus nodosus, A. obsoletus, Arhopalus rusticus nubilus, Asemum striatum, Monochamus titillator, Prionus pocularis, Xylotrechus integer, and X. sagittatus sagittatus. Buprestis lineata (Buprestidae), Alaus myops (Elateridae), and Hylobius pales and Pachylobius picivorus (Curculionidae) were also attracted to traps baited with (−)-α-pinene. In many locations, ethanol synergized attraction of the cerambycids Acanthocinus nodosus, A. obsoletus, Arhopalus r. nubilus, Monochamus titillator, and Xylotrechus s. sagittatus (but not Asemum striatum, Prionus pocularis, or Xylotrechus integer) to traps baited with (−)-α-pinene. Similarly, attraction of Alaus myops, Hylobius pales, and Pachylobius picivorus (but not Buprestis lineata) to traps baited with (−)-α-pinene was synergized by ethanol. These results provide support for the use of traps baited with ethanol and (−)-α-pinene to detect and monitor common large wood-boring beetles from the southeastern region of the USA at ports-of-entry in other countries, as well as forested areas in the USA.  相似文献   

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